I play with gut and alternate play each day. Advantage is the rackets feel the same. Disadvantage is that they will break close to the same time. You also have to be careful you will break both consecutively and will be without a racquet.

All strings lose tension every day even though not being played. Gut retains the best tension but has least durability.

they might pop at the same time, but it will take just as long to pop both by rotating them as it will to play with just one until it pops and then go to the other...so i would say rotate them...you might want to consider wiping down your strings each day with a rag to get the dirt off the strings...that causes friction which in turn will break the strings...

* the two-bin inventory system, or serial approach--play with one until it breaks, get it strung and play with the other.

* Alternately play with the racquets, or parallel approach.

An issue with the serial one is when to re-string. Re-string right away means tension loss before you need to play with it again. Delay the stringing and face the problem of finding yourself without any racquet in the middle of a match.

Another issue with the serial one is that you may be switching from lower tension and material fatigue to higher tension and fresher string.

The main issue with the parallel approach is the odds that at some time you will break strings on the same day or very close to that. On the positive side, you will more often be playing with strings about in the same condition so that when you break one frame, there's no adaptation period with the second frame.

Your choice .

Well, there is another option. Own 3 racquets and play them in parallel. That was my decision when I played more tournaments, after one day when I found myself with two frames with broken string and an ancient 3rd frame as backup.